"potentially being able to eavesdrop on our conversations", so now any app which has access to microphone "may be listening"?
So it uses data which you are willingly share with it to "serve better ads". Where is a problem with that? Does the author prefer worse ads?
I certainly do. I do not want ads at all, so I prefer them to be as least relevant to my interests as possible so the chances of them distracting me from what I was doing -- on the rare chance that my ad blocker fails -- are minimized.
I also don't like seeing ads about things I just looked at at Amazon on other websites. It gives me the impression that this new website I'm looking at knows what I'm shopping for.